Specimen positioning

ABSTRACT

An individual specimen positioner and a system for vacuum deposition of metal to prepare a specimen for observation by a scanning electron microscope. A number of specimens are held and positioned simultaneously, each positioned by an identical specimen positioner. Each specimen positioner has a grip for the specimen. The grip is mounted to a base through an angled shaft which is mounted on bearings to rotate the grip. The base is integrally connected to a vertical shaft, the axis of which extends through the center of gravity of the specimen. The vertical shaft is mounted on bearings to permit it to rotate the base. The vertical shaft is driven from a single motor which drives all of the several positioners in the same way. Perpendicular to the vertical shaft is a stationary crown gear. The angled shaft is positioned at a 45* angle with the horizontal, which in one position of rotation points that shaft directly at the evaporation source on a path which extends through the center of gravity of the specimen. The end of the angled shaft carries a pinion which meshes with the crown gear and thereby rotates the specimen through the action of the angled shaft as the specimen is also rotated by the vertical shaft. Rotation around the angled shaft is at more than five times the angular velocity of the rotation around the vertical shaft.

United-States Patent Tousimis [54] SPECIMEN POSITIONING [72] lnventor:Anastasios J. Tousimis, Rockville, Md. [73] Assignee: BrodynamicsResearch Corporation,

Rockville, Md.

[22] Filed: Aug. 7, 1969 [21] Appl. N0.: 848,299

[52] U.S.Cl ..ll8/48,118/53,269/57 [5| 1 Int. Cl ..C23c 13/08 [58] Fieldof Search ..1 Iii/48 49.5, 500, 118/503, 53, 56; 269/61, 71, 57; 279/5[56] References Cited UNITED STATES PATENTS 256,098 4/1882 Brooks..269/57 2,414,406 1/1947 Colbert et a1 ...l18/49 2,665,659 1/1954 Ogle,Jr. ..l18/49 3,031,339 4/1962 Regan, Jr. et a1. ..1 18/53 X 3,046,1577/1962 Nyman ....1 18/53 UX 3,128,205 4/1964 lllsley ..1 18/49 [4 1 Apr.18, 1972 [5 7] ABSTRACT An individual specimen positioner and a systemfor vacuum deposition of metal to prepare a specimen for observation bya scanning electron microscope. A number of specimens are held andpositioned simultaneously, each positioned by an identical specimenpositioner. Each specimen positioner has a grip for the specimen. Thegrip is mounted to a base through an angled shaft which is mounted onbearings to rotate the grip. The base is integrally connected to avertical shaft, the axis of which extends through the center of gravityof the specimen. The vertical shaft is mounted on bearings to permit itto rotate the base. The vertical shaft is driven from a single motorwhich drives all of the several positioners in the same way.Perpendicular to the vertical shaft is a stationary crown gear. Theangled shaft is positioned at a 45 angle with the horizontal, which inone position of rotation points that shaft directly at the evaporationsource on a path which extends through the center of gravity of thespecimen. The end of the angled shaft carries a pinion which meshes withthe crown gear and thereby rotates the specimen through the action ofthe angled shaft as the specimen is also rotated by the vertical shaft.Rotation around the angled shaft is at more than five times the angularvelocity of the rotation around the vertical shaft.

21 Claims, 7 Drawing Figures PATENTEDAPR 18 I972 FIG. 41:

. mmvron. ANASTASIOS J-TGJSMS BY I 6%;, HAM"...

ATTORNEY 1 SPECIMEN POSITIONING This invention relates to thepositioning of specimens during an operation from a source on thespecimens. More specifically, this invention relates to moving thespecimens during vacuum deposition of coating to achieve improvedcoating results, and is useful for many other purposes such as toachieve 360 diffraction of X-rays from a stationary source.

Deposition of evaporable substances by vapor deposition techniques uponitems positioned in an evacuated chamber is, of course, an art which ispracticed commercially for many purposes. These coatings may, amongother uses, serve decorative purposes, inhibit corrosion or wear,provide desirable optical properties, or provide a replication of thesurface coated in electrically conductive material.

The item or items to be coated are positioned in an evacuated chamberwhile deposition is conducted. The item may be moved during the coatingoperation. In some systems, the item is rotated so as to better coat alarger surface. Also, stepwise or continuous tilting stages areavailable commercially for rotating the surface on one axis between and90 to the source. The usual uses for these devices are for intentionalshadowing at low angles of incidence to accent surface irregularities.

The prior art does not teach a satisfactory technique to achieve acoating of very uniform thickness on a wide range of surfaceirregularities. Such a result is particularly important in certainspecialized, but highly significant, areas of operation. Of particularimportance in this regard is electron microscopy, particularly, scanningelectron microscopy.

In electron microscopy technology, a sample surface is coated asuniformly as practical with a thin film which is generally conductive.This layer should be as thin as possible in order to retain the image ofthe surface contour of the sample. At the same time, the coating shouldbe sufficiently thick to provide a continuous cover for purposes ofmechanical integrity and electrical conductivity.

In the microcosmic sense, virtually every item is rough and jagged. Whenitems are to be inspected with an electron microscope, such minuteunevenness is often the very point of interest.

Consequently, it is a primary object of this invention to provide meansto coat uneven items with conductive material with a coating which is atleast approximately even over a large part of the coated surface. It isan object to provide such an evenly coated surface, especially when thesurface contains very minute contours and roughness. The mechanisms inaccordance with this invention may be used for other important purposessuch as for X-ray diffraction studies on specimens held and moved in thesame manner as specimens to be coated.

Current practice is generally to evaporate material onto the surface tobe coated from a stationary source. The surface is positioned facing thesource at any angle 90 to the source. The rough and uneven parts of thesurface in such a system shadow parts of the surface and thereby hidethose parts from the source of emanations. The resulting coating is notof uniform thickness and may be discontinuous in many areas.

A more satisfactory coating is achieved in accordance with thisinvention by improved positioning of the specimen while usingconventional vacuum coating equipment. The specimen is moved during aconventional vacuum deposition operation so that an approximately evencoating is deposited on most of the surfaces being coated.

Consequently, it is a basic object of this invention to provide aspecimen positioner for a vapor deposition system which will cause thedeposition of an approximately even coating on a .large part of thesurface coated.

It is a further object .of this invention to-provide'such a specimenpositioner which is relatively small and compact.

It is a more general object of this invention to provide such a specimenpositioner which may be used simultaneously with other such positionersin a single vacuum deposition system.

It is another object of this invention to provide a specimen positionerin which during coating operations the distance between evaporant sourceand specimen is approximately constant, to thereby provide a more evencoating from the use of less complex mechanisms.

It is another, more specific object of this invention to provide aspecimen positioner which can turn the sample away from the evaporantsource, to thereby avoid the need for a shutter in a coating system.

In accordance with broad aspects of this invention, the specimenpositioner contains means to impart two different rotative movements tothe specimen. One movement tilts the entire specimen being coated todifferent angles relative to the source of emanations. As part of theoperation, the specimen is also rotated in a different plane to presentdifferent sides of contours on the surface facing the source.Topographic shadowing is thus circumvented.

' It is' another, more specific object of this invention to provide sucha specimen positioner which is economical, small,

and compact, and which can operate well with relatively heavy specimens.

Topographic shadowing is minimized by exposing the surface to evaporantfrom all directions. To approach that, the surface'should be rotated ina manner to present the full surface to the source at all angles fromand including 0 and At the same time, this surface should be rotatedaround an axis perpendicular to the surface. A greater variation inangles presented to the source is obtained as the angular velocityaround the perpendicular axis is increased relative to the velocity ofthe other rotation. Both rotative actions may be continued for anynumber of cycles, and a greater variation in angles is obtained as thecycles are continued when the two rotative movements are aperiodic, thatis, when the angular velocity around the perpendicular axis is not anintegral multiple of the other angular velocity.

The above mentioned and other objects, features, and ad vantages will bemade more apparent by the following detailed description of thepreferred embodiment of this invention, as illustrated by theaccompanying drawings.

FIG. 1 is a drawing which is merely illustrative of major fea turesrepresentative of the type of irregularities typically found on surfaceswith which this invention is concerned;

FIG. 2 illustrates the result of coating the surface of FIG. 1 by vacuumdeposition with emanations from one, stationary source. The blackoutlines in FIG. 2 illustrate the coating applied;

FIG. 3 is a detailed illustration of the preferred embodiment of onespecimen positioner assembly in accordance with this invention; 7

FIGS. 4a, 4b, and 4c show the preferred device in outline form in threeangular positions to illustrate the different movements involved in thepreferred embodiment of this invention;

FIG. 5 is illustrative of a plurality of the preferred specimen holdersin a system in which several of them operate simultaneously to coatdifferent specimens.

Reference is made to FIG. 1, which is intended to be merely illustrativeof the surface of a typical substrate. FIG. 1 is a sectional viewshowing the surface of an item 2 to be coated for subsequent examinationwith use of a scanning electron microscope. FIG. 1 shows the surface ofthe item 2 with random irregularities which may be somewhat circular asat 2a or may be jagged as at 20. It is desired to cover the surface ascompletely and evenly as possible with a very thin conductive coating.

FIG. 2 illustrates the results of coating the surface by deposition froma vacuum source when the source is simply positioned in a stationaryposition at 90 in relation to the surface being coated and deposition iscontinued until much of the surface is covered. Since parts are shadedor partially shaded by irregularities 2a and 20, those parts are coatedmuch more slowly or not at all, depending the extent of the shading bysurface irregularities. The solid black outline of coating in FIG. 2illustrates the position and thickness of the coating which results. Itis highly uneven and is discontinuous in many places. If deposition werecontinued, a more continuous coating could be achieved in many cases,but the coating would be much thicker in other areas with a consequentsubstantial loss in detail of the surface being coated.

STRUCTURE OF SINGLE POSITIONER FIG. 3 shows the details of one specimenpositioner in accordance with this invention. The specimen to be coatedis held by a grip 22, which is shown merely illustratively as it may beof any suitable construction, of which a number are presently known.Grip 22 is keyed or otherwise integrally linked to shaft 24. Shaft 24extends through holder base 26 and is appropriately mounted on bearings28 and 30 to freely rotate. At the bottom end of shaft 24, pinion gear32 is keyed or otherwise integrally linked to shaft 24.

In addition to providing support for shaft 24, base 26 extends as asingle unit to a position where vertical shaft 34 is received, which isat a position directly under the center of where grip 22 holdsspecimens. Vertical shaft 34 is keyed or otherwise integrally linked tobase 26. Shaft 34 extends through support member 36, and isappropriately mounted for movement on bearings 38. Crown gear 42 is acircular member mounted perpendicular to shaft 34 on top of supportmember 36.

The entire unit is held by plate 44, upon which member 36 is positioned.Plate 44 supports a number of the positioning units, each as shown inFIG. 3, and also may support or partially support the motor for drivingthe units as will be described. Plate 44 is firmly mounted to the frameof the vacuum deposition unit. This may be by any convenient device(none shown), many of which are within the state of the art.

Vertical shaft 34 extends freely through plate 44 and holds gear 46 nearits end. Gear 46 is integrally connected to shaft 34. Motor 48 ispositioned at the center of the coating area, generally under thelocation of evaporation source 50 and under plate 44 so that it isshielded from evaporant. Shaft 52 is driven by motor 48. Shaft 52 isintegral with large, power gear 54. Gear 54 links with gear 46 on thepositioning unit to provide the power for movement of the entireassembly. (No fundamental limitation is intended to be implied by thespecific location and linkage of motor 48 in this preferred embodiment.It is clear that the motor can be positioned in any number of locationsboth near and displaced from the coating area. Although the gearingarrangement used is an especially useful one, torque could be supplieddirectly to either shaft 24 or shaft 34, or motive power could besupplied by means basically different from that used in this preferredembodiment. When the motor is positioned outside of the evacuatedchamber used in the deposition process, it may be of a more conventionaldesign rather than of a design suited to operate in and maintain avacuum).

Evaporation source 50 is positioned above and spaced from the specimenpositioner assembly. Shaft 24 is generally perpendicular to the surfaceof items coated when held by grip 22. The angle of shaft 24 with thehorizontal is about 45, and shaft 24 points directly at evaporationsource 50 when grip 22 holds specimen 20 at 90 to source 50.

OPERATION OF SINGLE POSITIONER During the operation of a singlepositioner, a specimen 20, which may be a small biological specimen, isinserted so that it is held by grip 22. In the preferred embodiment,specimen 20 is shown as a thin, generally flat circular item. As isconventional, the area is evacuated and the vacuum source 50 is broughtto an elevated temperature to allow minute portions of conductivematerial to be evaporated from source 50 and to move of their ownmomentum to specimen 20.

Prior to or at an early time in the coating process, motor 48 is startedto thereby cause shaft 52 to rotate, which, in turn, causes rotation oflarge gear 54.

Large gear 54 is geared to vertical shaft 34 through gear 46. Thus,shaft 34 is rotated. Shaft 34 is integrally linked to base 26 and,through shaft 24 to grip 22. Therefore, grip 22, holding specimen 20 isrotated around a vertical axis which is coextensive with shaft 34. Thiscomponent or rotation moves the entire face of specimen 20 being coatedso that the entire face is continually presented to source 50 atdifferent angles. With continuous rotation in this manner, the angle atwhich emanations from source 50 reach the surface of specimen 20 willvary in a continuum from 0 to and back to 0, assuming a startingposition of 0 and sufiicient rotation of shaft 34.

As that rotative motion occurs, pinion gear 32 is forced alongstationary, crown gear 42. That interaction imparts a rotation to shaft24, which is directly translated to grip 22 and thereby to specimen 20.This second rotative movement is on an axis perpendicular to the surfaceof specimen 20 being coated. That rotative motion tends to presenttoward source 50 at different times all sides of irregularities on thesurface of specimen 20 being coated.

FIG. 4 shows in outline form a single specimen holder in three positionsso as to further illustrate the motions obtained and the positionsassumed. The structures and angular relationship between source 50 andspecimen 20 and grip 22 is the same as that of the system shown in FIG.3.

FIG. 4a is a view from the evaporative source 50 of the specimen at thestart of a coating cycle. At this position, which is preferred as thestarting position, specimen 20 is entirely turned away from source 50and is therefore not positioned to receive substantial amounts ofmaterial from source 50. It is therefore feasible to start theevaporation process and allow release of low vapor pressure contaminantsfrom the source as those released will not be directed toward thesurface of the specimen 20 to be coated. For that reason, a shutter isnot a necessary feature to minimize this initial contamination.

A point on the specimen labeled X for convenience is assumed to be atthe top of the specimen at this starting position. Almost any point onthe surface being coated would be as suitable for study as the oneselected since the entire surface of specimen 20 is rotated under theemissive source 50, primarily by the action of shaft 24, and it isrotation of that nature which is of interest in the tracing of point X.

When conditions are suitable for coating the surface, motion is impartedto the gear 46 through the action of gear 54, which is driven by motor48. Vertical shaft 34 is thereby rotated. FIG. 4b shows the positionobtained when shaft 34 has rotated clockwise 90. The rotation of shaft34 includes a component of rotation which has an axis perpendicular toan imaginery line from source 50 to specimen 20. That rotative motionhas tilted the entire surface of specimen 20 toward source 50.Simultaneously shaft 24 has rotated the specimen 20 relatively rapidlyaround an axis perpendicular to the surface being coated. One fullrevolution of that nature presents all sides of surface irregularitiesto source 50.

A ratio of about 5.1 to 1 exists between the diameter of crown gear 42and that of pinion gear 32. Consequently, shaft 24 is driven by gear 42at an angular velocity which is 5.1 times that of the angular velocityof shaft 34. That ratio yields a reasonably uniform coverage from allangles, but other ratios would be satisfactory and perhaps even betterin certain instances. The non-integral relationship of the two parts ofthe ratio assures that the motions obtained are aperiodic. In fact, themotions obtained will not produce an exact duplication of a previousposition until several revolutions of shaft 34 have occurred.

In FIG. 4b, shaft 34 has rotated 90 from the starting position. Shaft 24has therefore been rotated by gear 42, an amount of 5.1 times 90 or 459.That component of motion is the one of primary importance and interestin tracing the motion of specimen 20 around the axis perpendicular toits surface.

Shaft 34 is in a vertical position, and shaft 34 therefore inherentlyimparts a component of motion around the axis which is perpendicular tothe surface of specimen 20. As seen by source 50, that component ofmotion is an oscillation around the vertical axis at an angle whichappears to be somewhat larger than 45. That motion can be traced byconsidering the high point of specimen 20 observed as shaft 34 isrotated clockwise through the three positions shown in FIGS. 4a, 4b, and40. FIG. 4b illustrates the position after a 90 turn of shaft 34. Thehigh point of specimen 20 has moved clockwise to an angle somewhatgreater than 45 with the vertical. In FIG. 40, after a 180 turn of shaft34, the high point of specimen 20 once again appears at the center.

As mentioned, the component of motion directly imparted by shaft 34 onan axis perpendicular to the surface of specimen 20, is inherent. Therotation around that axis is largely dominated by the much greatermotion supplied by shaft 24. The corresponding component of rotation byshaft 34 will be mentioned and described only to a limited extent as isdesirable to assure completeness. However, to the extent that it is anincident to the relatively continuous and slow exposure of the specimenobtained in accordance with the more preferred aspects of thisinvention, that component of rotation should not be consideredumimportant.

Movement of the point X between the FIG. 4a position and the FIG. 4bposition is a combination of all components of mo tion.

Rotation directly in response to shaft 24 is 5.1 times the 90 movementof shaft 34, which is 459. The figure of 459 is representative, ofcourse, of the fact that all points on the surface of specimen 20 haverotated one complete circle and are 99 into the second circle. Thecorresponding rotative motion imparted directly by shaft 34 issubtractive. The position of point X is therefore at an acute angle onthe right above the horizontal, generally as illustrated in FIG. 4b.

FIG. 4c is the same view from source 50, this view being at the pointwhen shaft 34 has rotated 180. The surface being coated is thenpresented to source 50 at full face on a plane perpendicular to animaginary line from source 50 to specimen 20. Shaft 24 has rotated 918under the action of crown gear 42, and the component of rotation on thataxis directly from shaft 34 is zero. Total rotation around theperpendicular axis is therefore also 918. That is two full circles plus198. The position of the point X is at 198 as shown in FIG. 4c.

The total motion of particular significance can be described as being intwo parts. One is a component of rotative motion around an axisperpendicular to a line from source 50 to specimen 20, which presentsthe surface of specimen 20 at all angles of incidence to emanations fromsource 50. At the same time the other is a rotation around the axisperpendicular to the surface being coated, which tends to presentcontinually all sides of irregularities at all angles to emanations fromsource 50.

DISCUSSION AND CONCLUSION It will be noted that grip 22 is positionedand rotated on an angle so that at one point the specimen held is on aplane which approximately passes through the center of evaporationsource 50. The specimen positioned on that plane is the startingposition as shown and discussed in connection with FIG. 4a. Such aconfiguration has the advantage of providing posi tions of the specimenfrom fully hidden to fully open positions with a minimum of hiddenpositions. In fact, theoretically, the only hidden position is thestarting position. Rotation past that point presents the surface tosource 50, and the change in angle of the surface presented is slowrelative to the speed of rotation.

Of course, the face of the specimen to be coated may be mounted onstructures designed to provide no components of rotation except onecomponent on an axis perpendicular to the surface being coated and onecomponent on an axis perpendicular to a line from source 50 to thespecimen 20. In such a system, the rotation around the latter axis wouldhide the surface about half of the time. However, rarely are the rate ofmovement of the specimen or the amount of material which is depositedelsewhere than on the specimen, factors of great importance. Often, thespecimen can simply be rotated repetitively until coating is complete.Alternatively, the speed of rotation around the parallel axis can bereduced.

It will be noted that shaft 34 and shaft 24, the two shafts impartingrotative motion, are each on an axis which passes through the center ofspecimens held by grip 22. If the specimen held is symmetrical, eachaxis will pass through the center of gravity of the specimen, andproblems of momentum during operation will be minimized. Should an itembe irregular, an alternative method of operation would be to conduct therotation of shaft 34 intermittently. Rotation of shaft 34 is arelatively slow movement which need not be continuous. Rotation of shaft24 could still be continuous or, of necessary, that component could beintermittent.

The mechanism can be stopped in any position if coating from aparticular angle is desired for a special purpose.

In the preferred embodiment, the face of the specimen is presented at tothe source at one point in the coating cycle. At that point theapproximate center of the surface being coated is on a planeperpendicular to-a line from the source to the surface. Although similarresults could be obtained from other configurations, the highest coatingrate and more direct surface coverage does occur when that-position ispresented as part of the coating operation, since it presents the faceof the specimen most directly for coating.

However, in accordance with the broader aspects of this invention, theaxis around which the described rotations occur need not intersect thespecimen being rotated. One or more of the axes can be displaced, and alargely complete coverage of the specimen will occur basically aspreviously described. However, problems in angular momentum in rotatingon wide arcs will be apparent. Furthermore, such rotation tends to varysignificantly the distance of the sample from the source, and it isgenerally important to maintain a nearly constant distance to realize amore uniform coating.

FIG. 5 is illustrative of the system in a preferred form in which anumber of positioners identical to that discussed above are positionedin the same vapor deposition unit and operate simultaneously. Motor 48,through power gear 54 drives them all. (As previously mentioned, manyalternatives are possible in the supplying of power, and no fundamentallimitation is intended by the showing of the specific power mechanismsin the preferred embodiment.)

In an actual device, 6 positioners 70a-70f each capable of holding andpositioning a specimen of, for example, oneeighth inch by one-half inchin area have functioned with excellent results in a single vacuumcoating operation. All of the holders are supported by plate 44. All aredriven simultaneously by motor 48 through large gear 54 (seen in dottedoutline under plate 44).

In an exemplary embodiment, each holder is rotated at 5 rotations persecond by shaft 34. Copper is deposited from source 50 for the requiredperiod ranging from fractions of seconds to seconds depending onthickness desired. Most metals, alloys of metals, and carbon are capableof evaporation by, for example, electron beam evaporation or sputteringtechniques. Generally the motor must be capable of operating in a vacuumof at least 10 torr. Examples of materials coated are: aluminum, copper,silicon, silicon dioxide, uranium,

platinum, copper and gold-palladium alloy. Deposition of sil-.

icon and silicon dioxide and conductive metals is significant for themanufacture of solid state circuits.

It will be apparent from the nature of the invention and the aboveteachings that the broader aspects of the invention herein described arenot limited by the specifics of the structure shown. Consequently,reference should be made to the following claims, properly interpretedaccording to law, for the limits of the coverage sought.

What is claimed is:

l. A vapor deposition apparatus comprising in combination:

a vapor source;

a laterally extending, fixed means vertically spaced from,

and on an axis common with said source;

at least one specimen support assembly disposed on a peripheral portionof said fixed means and in facing relationship with said source;

said support assembly having a body portion rotatably mounted on avertically disposed shaft supported on said fixed means;

said rotatable body including means supporting a rotatable shaftextending therethrough at an inclination to said shaft and towards saidsource;

a specimen holder means fixed at its center, to the upper and inwardlydirected end of said inclined shaft and in a plane normal to saidinclined shaft;

said shafts, body and holder being so structurally related that thecenter of said specimen holder and specimen coincides with the extendedaxis of said vertically disposed shaft;

a stationary gear means concentric with said vertically disposed shaft;

a second gear means fixed to the outer end of said inclined shaft and inoperative association with said stationary gear means;

means to rotate said vertical shaft whereby (1) said body is rotatedabout the vertical shaft; (2) said second gear means is carried aboutsaid stationary gear means; (3) said specimen is rotated about its ownaxis while nutating with respect to said extended axis; and

whereby a uniform deposition is effected upon said nutating specimen asit is carried progressively through positions wherein the specimensurface lies in a plane normal to a vapor stream emanating from saidsource and in a plane parallel to said stream 2. The combination ofclaim 1 comprising a plurality of said specimen support assemblies anddrive means therewith disposed at peripheral portions of said laterallyextending fixed means.

3. The combination of claim 2 wherein said plurality of specimen supportassemblies are driven by the same power source.

4. The combination of claim 1 wherein said means to rotate around saidinclined shaft provides a rotation of at least twice the angularvelocity of the angular velocity of the rotation provided by said meansto rotate around said vertical shaft.

5. The combination of claim 4 wherein said means to rotate around saidvertical shaft provides a rotation of at least 90".

6. The combination of claim 5 wherein said means to rotate around saidinclined shaft providesa rotation of at least four times the angularvelocity of the angular velocity of the rotation provided by said meansto rotate around said vertical shaft.

7. The combination of claim 6 wherein said means to rotate around saidinclined shaft provides a rotation of angular velocity which is anon-integral multiple of the angular velocity of the rotation providedby said means to rotate around said vertical shaft.

8. The combination of claim 1 wherein said source comprises anevaporable material for vacuum deposition.

9. The combination of claim 8 wherein said means to rotate around saidinclined shaft provides a rotation of at least twice the angularvelocity of the angular velocity of the rotation provided by said meansto rotate around said vertical shaft.

10. The combination of claim 9 wherein said means to rotate around saidinclined shaft provides a rotation of angular velocity which is anon-integral multiple of the angular velocity of the rotation providedby said means to rotate around said vertical shaft.

11. The combination of claim 9 wherein said means to rotate around saidvertical shaft provides a rotation of at least 12. The combination ofclaim 11 wherein said means to rotate around said inclined shaftprovides a rotation of angular velocity which is anon-integjral multipleof the angular velocity of the rotation provi ed by said means to rotatearound said vertical shaft.

13. The combination of claim 11 wherein said means to rotate around saidinclined shaft provides a rotation of at least four times the angularvelocity of the angular velocity of the rotation provided by said meansto rotate around said vertical shaft.

14. The combination of claim 13 wherein said means to rotate around saidinclined shaft provides a rotation of angular velocity which is anon-integral multiple of the angular velocity of the rotation providedby said means to rotate around said vertical shaft.

15. The combination of claim 14 wherein a driving means power said meansto rotate said vertical shaft and the changes of position of saidsupport assembly around said vertical shaft are transmitted by astationary ring gear linked through said second gear means to saidinclined shaft to move said specimen around said extended axis.

16. The combination of claim 14 wherein said ring gear is a crown gear.

17. The combination of claim 14 wherein said second gear means is apinion gear.

18. The combination of claim 2 wherein said vapor source is the commonsource for the plurality of said specimens.

19. The combination of claim 6 including a plurality of said specimensupport assemblies and drive means therewith disposed at peripheralportions of said laterally extending fixed means and said vapor sourceis the common source for the plurality of said specimens.

20. The combination of claim 8 including a plurality of said specimensupport assemblies and drive means therewith disposed at peripheralportions of said laterally extending fixed means and said vapor sourceis the common source for the plurality of said specimens.

21. The combination of claim 13 including a plurality of said specimensupport assemblies and drive means therewith disposed at peripheralportions of said laterally extending fixed means and said vapor sourceis the common source for the plurality of said specimens.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 656,453 Dated April 18 1972 Inventor(s) Anastasios J. Tousimis It iscertified that error appears iri the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

1. On Title Page, Assignee: "Brodynamics" should read --Biodynamics--.

Signed and sealed this 17th day of October 1972.

(SEAL) Attest:

EDWAROMELETCHERJR. ROBERT GOTTSOHALK Attesting Officer Commissioner ofPatents USCOMM-DC 60376-P69 a us GOVERNMENT PRINTING OFFICE: I9590-366-334 FORM PO-105O (10-69)

1. A vapor deposition apparatus comprising in combination: a vaporsource; a laterally extending, fixed means vertically spaced from, andon an axis common with said source; at least one specimen supportassembly disposed on a peripheral portion of said fixed means and infacing relationship with said source; said support assembly having abody portion rotatably mounted on a vertically disposed shaft supportedon said fixed means; said rotatable body including means supporting arotatable shaft extending therethrough at an inclination to said shaftand towards said source; a specimen holder means fixed at its center, tothe upper and inwardly directed end of said inclined shaft and in aplane normal to said inclined shaft; said shafts, body and holder beingso structurally related that the center of said specimen holder andspecimen coincides with the extended axis of said vertically disposedshaft; a stationary gear means concentric with said vertically disposedshaft; a second gear means fixed to the outer end of said inclined shaftand in operative association with said stationary gear means; means torotate said vertical shaft whereby (1) said body is rotated about thevertical shaft; (2) said second gear means is carried about saidstationary gear means; (3) said specimen is rotated about its own axiswhile nutating with respect to said extended axis; and whereby a uniformdeposition is effected upon said nutating specimen as it is carriedprogressively through positions wherein the specimen surface lies in aplane normal to a vapor stream emanating from said source and in a planeparallel to said stream.
 2. The combination of claim 1 comprising aplurality of said specimen support assemblies and drive means therewithdisposed at peripheral portions of said laterally extending fixed means.3. The combination of claim 2 wherein said plurality of specimen supportassemblies are driven by the same power source.
 4. The combination ofclaim 1 wherein said means to rotate around said inclined shaft providesa rotation of at least twice the angular velocity of the angularvelocity of the rotation provided by said means to rotate around saidvertical shaft.
 5. The combination of claim 4 wherein said means torotate around said vertical shaft provides a rotation of at least 90*.6. The combination of claim 5 wherein said means to rotate around saidinclined shaft provides a rotation of at least four times the angularvelocity of the angular velocity of the rotation provided by said meansto rotate around said vertical shaft.
 7. The combination of claim 6wherein said means to rotate around said inclined shaft provides arotation of angular velocity which is a non-integral multiple of theangular velocity of the rotation provided by said means to rotate aroundsaid vertical shaft.
 8. The combination of claim 1 wherein said sourcecomprises an evaporable material for vacuum deposition.
 9. Thecombination of claim 8 wherein said means to rotate around said inclinedshaft provides a rotation of at least twice the angular velocity of theangular velocity of the rotation provided by said means to rotate aroundsaid vertical shaft.
 10. The combination of claim 9 wherein said meansto rotate around said inclined shaft provides a rotation of angularvelocity which is a non-integral multiple of the angular velocity of therotation provided by said means to rotate around said vertical shaft.11. The combination of claim 9 wherein said means to rotate around saidvertical shaft provides a rotation of at least 90*.
 12. The combinationof claim 11 wherein said means to rotate around said inclined shaftprovides a rotation of angular velocity which is a non-integral multipleof the angular velocity of the rotation provided by said means to rotatearound said vertical shaft.
 13. The combination of claim 11 wherein saidmeans to rotate around said inclined shaft provides a rotation of atleast four times the angular velocity of the angular velocity of therotation provided by said means to rotate around said vertical shaft.14. The combination of claim 13 wherein said means to rotate around saidinclined shaft provides a rotation of angular velocity which is anon-integral multiple of the angular velocity of the rotation providedby said means to rotate around said vertical shaft.
 15. The combinationof claim 14 wherein a driving means power said means to rotate saidvertical shaft and the changes of position of said support assemblyaround said vertical shaft are transmitted by a stationary ring gearlinked through said second gear means to said inclined shaft to movesaid specimen around said extended axis.
 16. The combination of claim 14wherein said ring gear is a crown gear.
 17. The combination Of claim 14wherein said second gear means is a pinion gear.
 18. The combination ofclaim 2 wherein said vapor source is the common source for the pluralityof said specimens.
 19. The combination of claim 6 including a pluralityof said specimen support assemblies and drive means therewith disposedat peripheral portions of said laterally extending fixed means and saidvapor source is the common source for the plurality of said specimens.20. The combination of claim 8 including a plurality of said specimensupport assemblies and drive means therewith disposed at peripheralportions of said laterally extending fixed means and said vapor sourceis the common source for the plurality of said specimens.
 21. Thecombination of claim 13 including a plurality of said specimen supportassemblies and drive means therewith disposed at peripheral portions ofsaid laterally extending fixed means and said vapor source is the commonsource for the plurality of said specimens.